Laughing Falcons (Herpetotheres cachinnans), are known to feed primarily on snakes, although there are reports in the literature of the falcons feeding on other prey. In the present study in the semi-arid scrublands of the Brazilian Caatinga, two predation events were recorded in which Laughing Falcons captured small-bodied mammals, a marmoset (Callithrix jacchus) and a rock cavy (Kerodon rupestris), both estimated to be approximately 200–300 g in weight. In both cases, the mammals were juveniles; the falcon swooped down to capture the prey in its talons, then it flew off to feed some distance away. While these events suggest a shift in the feeding niche of the falcon in response to local conditions, the number of observations is too small to permit definitive conclusions on this phenomenon.